export const getmark = () => {
 
  const setWatermark = (str: any) => {
 
    const id = "1.23452384164.123412416";
 
 
    if (document.getElementById(id) !== null) {
 
      document.body.removeChild(document.getElementById(id)!);
 
    }
 
 
 
    //创建一个画布
 
    const can = document.createElement("canvas");
 
    //设置画布的长宽

    can.width = 170;

    can.height = 150;
 
 
 
    const cans = can.getContext("2d")!;
 
    //旋转角度
 
    cans.rotate((-36 * Math.PI) / 180);
 
    cans.font = "14px PingFang SC";
 
    //设置填充绘画的颜色、渐变或者模式
 
    cans.fillStyle = "rgba(200, 200, 200, 0.25)";
 
    //设置文本内容的当前对齐方式
 
    cans.textAlign = "left";
 
 
    //在画布上绘制填色的文本（输出的文本，开始绘制文本的X坐标位置，开始绘制文本的Y坐标位置）
 
    cans.fillText(str, can.width / 8, can.height / 2);
 
 
 
    const div = document.createElement("div");
 
    div.id = id;
 
    div.style.pointerEvents = "none";
 
    div.style.top = "100px";
 
    div.style.left = "0px";
 
    div.style.position = "fixed";
 
    div.style.zIndex = "0";
 
    div.style.width = document.documentElement.clientWidth + "px";
 
    div.style.height = document.documentElement.clientHeight + "px";
 
    div.style.background =
 
      "url(" + can.toDataURL("image/png") + ") left top repeat";
 
    document.body.appendChild(div);
 
    return id;
 
  };
 
 
 
  // 该方法只允许调用一次
 
  const watermark = (str: string) => {
 
    let id = setWatermark(str);
 
    setInterval(() => {
 
      if (document.getElementById(id) === null) {
 
        id = setWatermark(str);
 
      }
 
    }, 500);
 
    window.onresize = () => {
 
      setWatermark(str);
 
    };
 
  };
 
  return { watermark };
 
}; 